Days Set Up
Analytic Time

24 - 48 hours after isolation of specific organism to be tested or isolate received

MiChart Code
Sensitivity Only
Soft Order Code

Test Updated:


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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

The susceptibility methodology is dependent on the site of infection and/or the organism. In most cases, an MIC will be performed. Disk diffusion (Kirby-Bauer) will be performed on organisms such as mucoid pseudomonas, stenotrophomonas, Pseudomonas aeruginosa from CF patients, and if susceptibility is requested for additional drugs not available using the MIC methodology. Extended spectrum beta-Lactamase testing will be performed on Gram negative bacteria when indicated by susceptibility pattern. Beta-Lactamase testing (enzyme detection) will be performed on Gram positive bacteria when indicated by susceptibility pattern.

Test Usage

To determine susceptibility of a given organism to a panel of antimicrobic agents.

Reference Range

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Offsite

For all cultures, susceptibility testing is performed automatically on potentially pathogenic organism(s) at an additional charge unless specifically declined. To request susceptibility testing using antibiotics not normally tested, call the MLabs Client Services Center. Organisms will be held up to 7 days from the date specimen was received. For testing on actively growing organisms: 1) Aerobic Bacteria: Swab organism from pure culture and send swab in aerobic transport tube. Do not send plate. Transport at room temperature. (Swabs sent in aerobic transport do not require two-pouch SAF-T-PAK system.) 2) Anaerobic Bacteria: Place actively growing organism on anaerobic plate in an anaerobic transport bag. Place inside clear, liquid tight SAF-T-PAK bag and seal tape liner. Place sealed bag and requisition inside white biohazard SAF-T-PAK envelope and seal. Transport at room temperature.

Minimum Volume

Billing Information

CPT Code
87186 MIC, 87184 KB, 87184 ESBL, 87185 BLFEE
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.